The liquid portion was decanted and the solid was dried in an oven for 24 h at 105 ◦C. The resulting adsorbent was then used in the experiment without further grinding and sieving. The scanning electron micrograph (Fig. 1) of the untreated and treated oil palm fibre shows a change from fibre to grains with cavities. The Fourier transform infrared spectroscopy (FTIR) results show adsorption bands of hydroxyl, carbonyl and aliphatic groups.